This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 11-162565, filed Jun. 9, 1999, the entire contents of which are incorporated herein by reference.
The present invention relates to a substrate processing apparatus and method for performing processing such as developing processing or the like for a substrate such as a semiconductor wafer or the like while sending air in a processing chamber.
In a photolithography process of a semiconductor device, a semiconductor wafer is coated with a resist, a resist film formed by the coating process is exposed in accordance with a predetermined circuit pattern, and the exposed pattern is developed, whereby a circuit pattern is formed on the resist film.
To perform such a series of processes, hitherto a resist coating and developing processing system has been used. Such a resist coating and developing processing system includes a processing station, a cassette station and an interface section, which are integrally provided. Various processing units for performing various kinds of processing for coating and developing for a wafer are multi-tiered in the cassette station. The cassette station has cassettes for housing a plurality of semiconductor wafers, carrying the semiconductor wafers into the processing station one by one and carrying the processed semiconductor wafer out of the processing station and housing it in a cassette. The interface section receives and passes the wafer from and to an aligner disposed adjacent to the system, for exposing a resist film in a predetermined pattern.
In such a resist coating and developing processing system, wafers are taken out of the cassette placed in the cassette station one by one and transferred to the processing station. The wafer is first subjected to hydrophobic processing in an adhesion processing unit and cooled in a cooling processing unit, and thereafter coated with a photoresist film in a resist coating unit and subjected to baking processing in a heat processing unit.
Thereafter, the semiconductor wafer is transferred to the aligner from the processing station via the interface section, and the resist film is exposed in a predetermined pattern in the aligner. After exposure, the semiconductor wafer is transferred again to the processing station via the interface section. The exposed semiconductor wafer is first subjected to post-exposure bake processing in the heat processing unit and cooled, and thereafter coated with a developing solution in a developing processing unit, whereby the exposed pattern is developed. Then, the semiconductor wafer is subjected to post-bake processing in the heat processing unit and cooled, and thus a series of processing is completed. After the completion of the series of processing, the semiconductor wafer is transferred to the cassette station and housed in the wafer cassette.
In the developing unit which is a rotary system processing unit in the aforesaid coating and developing system, the wafer which has undergone the bake processing and cooling processing after being exposed is mounted on a spin chuck in a processing chamber, and a developing solution is supplied to the wafer and applied over the entire face of the wafer, for example, so as to have a thickness of 1 mm. The developing solution stands still for a predetermined period of time while being applied onto the wafer, and developing processing is progressed by natural convection. Thereafter, the wafer is rotated by the spin chuck, and thereby the developing solution is blown off. Thereafter, a rinse solution is discharged to wash away the developing solution remaining on the wafer. The spin chuck is then rotated at a high speed, thereby the developing solution and the rinse solution remaining on the wafer are blown away, and the wafer W is dried.
Incidentally, in such a developing process, clean air is sent into the processing chamber of the developing unit from the top thereof via a filter and exhausted from the bottom of the processing chamber, thus forming the down flow of clean air in the processing chamber. However, when the developing solution stands still for a predetermined period of time while being applied over the entire face of the wafer, exhaust operation is stopped in order to prevent a change in temperature, and the exhaust operation is resumed just before the standstill of the developing solution concludes. When the exhaust operation is stopped during the standstill of the developing solution as above, however, the pressure in the processing chamber of the developing unit rises.
In the case where the wafer is carried into the developing unit, when a wafer transfer device reaches the front of a shutter of the developing unit, the shutter is opened, and the wafer is delivered to the spin chuck by the wafer transfer device, but the pressure in the processing chamber of the developing unit drops when the shutter is opened.
Such a change in pressure is conventionally not so important to developing processing. In recent years, however, with high integration of devices, patterns become more minute, and developing units are downsized in terms of saving space, whereby there is a possibility that a change in pressure in the processing chamber as described above exerts an influence on developing processing.
An object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of preventing a change in pressure in the processing chamber to the utmost and eliminating a bad influence on processing accompanying the change in pressure.
To settle the aforesaid disadvantage, according to a first aspect of the present invention, a substrate processing apparatus comprises a processing chamber configured to perform predetermined processing for a substrate therein, a blast unit configured to send gas into the processing chamber from the top toward the bottom thereof, an exhaust unit configured to perform exhaust operation from within the processing chamber through the bottom thereof, and a control unit configured to regulate a blast amount of the blast unit and/or an exhaust amount of the exhaust unit concomitantly with a change in pressure in the processing chamber to maintain the pressure in the processing chamber nearly constant.
According to the aforesaid structure, even when the pressure in the processing chamber is prone to change due to downsizing of the processing unit, the blast amount and/or the exhaust amount is regulated concomitantly with the change in pressure to thereby maintain the pressure in the processing chamber nearly constant. As a result, a change in pressure in the processing chamber can be prevented to the utmost, and an influence accompanying the change in pressure can be eliminated.
According to a second aspect of the present invention, a substrate processing apparatus comprises a processing chamber configured to perform predetermined processing for a substrate therein, a blast unit configured to send gas into the processing chamber from the top toward the bottom thereof, an exhaust unit configured to perform exhaust operation from within the processing chamber through the bottom thereof, a carrying in/out port configured to carry the substrate into the processing chamber and out of the processing chamber, a shutter configured to open and close the carrying in/out port, and a control unit configured to perform such control that a blast amount of the blast unit is increased or an exhaust amount of the exhaust unit is decreased concomitantly with the opening of the shutter when the shutter is opened to maintain pressure in the processing chamber nearly constant.
According to the aforesaid structure, even when the pressure in the processing chamber is prone to change with the opening and closing of the shutter for carrying the substrate to be processed in and out due to downsizing of the processing unit, such a control that the blast amount is increased or the exhaust amount is decreased concomitantly with the opening of the shutter when the shutter is opened is performed to thereby maintain the pressure in the processing chamber nearly constant. Consequently, a drop in pressure at the time of opening of the shutter can be compensated and a change in pressure in the processing chamber can be prevented to the utmost, thereby eliminating an influence accompanying the change in pressure.
According to a third aspect of the present invention, a substrate processing apparatus comprises a processing chamber configured to house a substrate, a processing solution supply mechanism configured to supply a processing solution to the substrate in the processing chamber, a blast unit configured to send gas into the processing chamber from the top toward the bottom thereof, an exhaust unit configured to perform exhaust operation from within the processing chamber through the bottom thereof, and a control unit configured to stop the exhaust operation of the exhaust unit during a predetermined period of time after the processing solution is supplied to the substrate and concomitantly with the stop of the exhaust operation and decrease a blast amount of the blast unit, thereby maintaining pressure in the processing chamber nearly constant.
According to the aforesaid structure, when solution processing using a processing solution is performed for the substrate, during a predetermined period of time after the processing solution is supplied to the substrate, the exhaust operation of the exhaust unit is stopped in order to prevent a change in temperature and the like, and even when a rise in pressure in the processing chamber arises due to the stop of the exhaust operation, since the blast amount of the blast unit is decreased concomitantly with the stop of the exhaust operation of the exhaust unit to thereby maintain the pressure in the processing chamber almost constant, the rise in pressure following the stop of the exhaust operation can be compensated, and a change in pressure in the processing chamber can be prevented to the utmost, thereby eliminating an influence accompanying the change in pressure.
According to a fourth aspect of the present invention, a substrate processing method for performing predetermined processing for a substrate in a processing chamber, comprises the steps of performing blast operation of sending gas into the processing chamber from the top toward the bottom thereof and performing exhaust operation from within the processing chamber through the bottom thereof, and during the blast and exhaust operation, controlling at least one of the blast operation and the exhaust operation concomitantly with a change in pressure in the processing chamber to maintain the pressure in the processing chamber nearly constant.
According to a fifth aspect of the present invention, a substrate processing method for performing predetermined processing for a substrate in a processing chamber, comprises the steps of performing blast operation of sending gas into the processing chamber from the top toward the bottom thereof and performing exhaust operation from within the processing chamber through the bottom thereof, during the blast and exhaust operation, opening a shutter for opening and closing a carrying in/out port for carrying the substrate in and out, and when the shutter is opened, concomitantly with the opening of the shutter, increasing a blast amount or decreasing an exhaust amount to maintain pressure in the processing chamber nearly constant.
According to a sixth aspect of the present invention, a substrate processing method for supplying a processing solution to a substrate to perform predetermined solution processing for the substrate while blast operation of sending gas into the processing chamber from the top toward the bottom thereof is performed with exhaust operation through the bottom thereof being performed, comprises the steps of stopping the exhaust operation during a predetermined period of time after the processing solution is supplied to the substrate, and concomitantly with the stop of the exhaust operation, decreasing a blast amount to maintain pressure in the processing chamber nearly constant.
According to the structures of the fourth to sixth aspects of the present invention, the same effects as the first to third aspects have can be obtained.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.